Two new Opadometa species (Araneae: Tetragnathidae) from Sarawak, Malaysia
Author
Dzulhelmi, Muhammad Nasir
Author
Suriyanti, Su
Author
Zulqarnain, Mohamed
Author
Norma, Che Yusoff
text
Annales Zoologici
2015
65
101
107
journal article
10.3161/00034541anz2015.65.1.008
55eab727-20e9-4593-a2b9-92f2473f1b63
1184737
Opadometa kuchingensis
Dzulhelmi et Suriyanti
,
sp. nov.
Etymology
. The specific name is a noun, referring to the division in Sarawak where the
holotype
was collected.
Diagnosis
. The
O. kuchingensis
resembles
O. fastigata
and
O. sarawakensis
but can be differentiat- ed by the following:
Epigyne
: (1) The
O. kuchingensis
have shorter copulatory duct while
O. sarawakensis
copulatory ducts are more than half the spermathecae length
Abdomen:
(2) The
O. kuchingensis
has an oval abdomen that does not overhang the carapace while
O. fastigata
and
O. sarawakensis
has a pear-shaped abdomen and strongly overhangs the carapace.
Legs:
(3) The
O. kuchingensis
and
O. sarawakensis
have dense brush of hairs on tibia I and IV while
O. fastigata
has dense hairs on tibia IV only.
Description
.
Female
. Total length 7.05;
Carapace
: 3.33 long, 2.20 wide. Carapace light-brown in colour, carapace longer than wide (approximately 70%), cephalic area slightly narrower or nearly equal to thoracic area, sternum dark-brown in colour and slightly longer than wide in length, 1.27 long, 1.24 (
Fig. 17
).
Eyes
: diameters AME 0.18, ALE 0.10, PME 0.18, PLE 0.10; inter-distances AME–AME 0.14, AME–ALE 0.43, PME–PME 0.11, PME–PLE 0.36, PLE–PLE 0.10, AME–PME 0.21; clypeus 0.21 high. Lateral eyes loosely contiguous or almost so, eight eyes in slightly two recurved rows. PME slightly shorter than AME, distance between PME slightly shorter than between AME, PME size greater than distance between them, AME size about the same as distance between them, distance between PME and PLE are about two times the PME eye size (
Fig. 16
).
Chelicerae
: Promargin with series of 4 teeth, retromargin with series of 3 teeth (
Figs 14, 15
).
Abdomen
: abdomen 3.78 long, 2.44 width; Pear-shaped abdomen not overhanging the cephalothorax, light-orange abdomen colour with darker orange marking covering one third of the dorsal end of the abdomen, with black marking at the tip of the abdomen (
Fig. 19
).
Spinnerets
: Spinnerets at ventral tip of abdomen, tip of spinneret facing downward and does not exceed end of abdomen.
Legs
: Legs light-brown in colour with black annulations, Leg formula (
I
–
II
–
IV
–
III
), leg measurements (femur/ patella/ tibia/ metatarsus / tarsus/ total): leg I (4.78/1.11/4.01/5.44/ 1.56/16.90), leg II (4.01/1.02/3.22/3.89/1.22/13.36), leg III (2.44/0.68/ 1.56/2.02/0.89/7.59), and leg IV (4.44/0.89/ 3.00/3.78/ 1.11/13.22). Short spines on legs, Leg I: femur I with 3–5 spines, tibia I wit 3–4 spines, dense brush hairs covering more than one-third of the tibia, Leg II: femur II with 1–2 spines, tibia II with 3–4 spines, very few brush hairs covering more than one-third of the tibia, one row of short trichobothria covering half of retrolateral femur II, Leg III: femur III with 1–2 spines, tibia III with 3–4 spines, one row of short trichobothria covering more than two third of prolateral femur III; Leg IV: femur IV with 1–2 spines, tibia 4 with 3–4 spines, dense brush hairs covering more than one-third of the tibia, two rows of long trichobothria covering more than one third of the prolateral femur IV (
Fig. 18
).
Epigyne
: Epigyne simple and weakly sclerotized, spermathecae ovate and mushroom-like in shape, copulatory duct shorter than spermathecae in length (
Figs 20, 21
).
Figures 5–13. Female
Opadometa sarawakensis
new species
. Eye pattern: (5) dorsal view, (6) frontal view; female body: (7) ventral view, (8) dorsal view, (9) lateral view; right teeth: (10) inner view, (11) lateral view; epigyne: (12) dorsal view (internal), (13) ventral view (outer).
Figures 14–21. Female
Opadometa kuchingensis
new species
. Right teeth: (14) prolateral view, (15) ventral view; Eye pattern: (16) frontal view; female body: (17) ventral view, (18) dorsal view, (19) lateral view; epigyne: (20) dorsal view (internal), (21) ventral view (outer).
Table 1. Web characters of
O. sarawakensis
and
O. kuchingensis
.
| Web characters |
O. sarawakensis
|
O. kuchingensis
|
| Web diameters, vertical/horizontal |
33.5 cm, 30.69 cm |
14.74 cm, 22.03 cm |
| Number of radii |
39 |
24 |
| Number of spirals |
62–70 |
24–28 |
| Mesh size |
0.18–0.29 cm |
0.23–0.36 cm |
| Hub diameter, Vertical / horizontal |
2.48 cm, 2.25 cm |
1.94 cm, 2.03 cm |
| Free-zone diameter, Vertical / horizontal |
3.96 cm, 3.67 cm |
3.99 cm, 5.70 cm |
| Web area |
779.87 cm2 |
181.93 cm2 |
| Free-zone area |
29.84 cm2 |
19.46 cm2 |
| Hub-area |
4.77 cm2 |
1.17 cm2 |
| Height from ground |
200 cm |
200 cm |
Figures. 22–23. (22) Web of
O. sarawakensis
; (23) Web of
O. kuchingensis
.
Male
. Unknown.
Type material.
Female
holotype
(
BNP005
) from
Bako National Park
,
Sarawak
,
Malaysia
(
1°41’N
,
110°26’E
) was collected by
hand-picking
(Collector:
Dzulhelmi Nasir
) during the daytime at
11:30
hours on
27th April 2013
.
Distribution
. It is only known from the
type
locality at the lowland dipterocarp forest in Sarawak.
Natural history
. Diurnal. The spiders were found resting at the center of its hub during the day light. The webs were constructed at 45° angle at an open space above
200 cm
from ground which was covered with dense shrubs. Premature female of similar species were also found at close proximity to where this adult female was caught.